1. Field of the Invention
The present invention relates to the driving system of a copying machine and more particularly to the driving system of the optical system for the exposure that optically scans the document.
2. Description of the Prior Art
In the past, the driving and controlling of the optical system for exposure having a function of a forward and backward traveling that optically scans the document have been done through the electromagnetic clutch for the forward movement that takes charge of the forward traveling of the optics unit for exposure and the electromagnetic clutch for the backward movement that takes charge of the backward traveling of the optical system for exposure both are incorporated in the driving system extending over the driving motor and the optical system for exposure and are further controlled by signals such as a commanding signal for copying and a signal of a limit switch such as a microswitch and others.
With such a structure, however, the manufacturing cost of a copying machine tends to be comparatively high due to the introduction of an electromagnetic clutch and a relay which are expensive.
In a U.S. patent application Ser. No. 464,903 filed on Feb. 8th 1983, there is proposed a driving system of the optical system for exposure wherein no expensive electromagnetic clutch and others are used and that the paper-feeding members such as a paper-feeding roller and others may be controlled mechanically in the driving system of the optical system for exposure.
However, even in the research and development for the driving system of the optical system for exposure, there has been a fear that the recording paper for the next cycle will be conveyed to the paper-supply path by the paper-supply member during the period of copy operation in the previous cycle when the optics unit for exposure is operated again without any waiting time during the continuous copying because the paper-feeding member is kept in the driving condition until the optical system for exposure returns almost perfectly to its original position. In the aforesaid driving system of the optical system for exposure, therefore, the waiting time that means the momentary stop of the optical system for exposure is set for continuous copying thus the erroneous feeding of the recording paper is prevented. With such measures, however, the number of copies produced per certain period of time is reduced due to the setting of the waiting time thereby there is a limitation for the efficient copying.